I would mount the exchange to the front or back of the box, leaving it sealed. You won't get any natural convection so you can either induce it, or rely on conduction coping with the low heat output. Those nano boards can run on just a few watts.

not really related but if you guys need any help with FEC on your telemetry streams i've been working with reed solomon and convolutional codes since last year and can help you get them right on the first try without having to figure it out yourself, an easy task in the latter case and not so easy one in the former.